I grew up in Columbus. (More or less) Left about 20 years back, so I
don't have any current connections, but there are two people I'd
(A) Werkhaven's. (If you haven't found them yet, you should) Only
real jewelry supply house in the area. North High, just short of
They don't do diamonds, but if anybody in the area does, they'd know
who. (They might not tell you until you prove that you're for real,
but that's up to you.)
(B) Orchid's own 'Goo'. (Gustavo Hoefs). Runs a very nice little
custom jewelry shop in Beechwold. On High, just south of Morse.
(Beechwold Custom Jewelry. http://www.ganoksin.com/gnkurl/ep806y
it means anything, when my mom needed a ring worked on and I
couldn't get to it, I sent her to Goo. He might be able to hook you
in to the locals.
For whatever that all's worth.